Road finishing machine



June 15, 1937. w. u. VINTON ROAD FINISHING MACHINE Filed March 1'7, 19344 Sheets-Sheet 1 June 1937- w. u. VINTON 2,084,06

ROAD FINISHING MACHINE Filed March 17, 1934 4 Sheei s;Sheet 2 .fm/entorWilliam [1. Vz'nzon y %gj% A Ztorney June-35,, 1937. w. u. VHNTON ROADFINISHING MACHINE- Filed March 17, 1934 4 Sheets-Sheet 3 Attor ey W. U.VINTON ROAD FINISHING MACHINE June 15, 137

4 Sheets-.-Shee. 4

Filed March 17, 1934 Inventor William H Vinton Attorney Patented in...15, 1937 UNETED STATES PATENT oFFlcE 21 Claims.

The invention provides a continuous longitudinal road finishing machine,that is to say, a machine for use in the forming of concrete roads andthe like, its screed lying longwise of the roadway, and its action beingautomatic and continuous.

The operations that are usual in laying concrete roads, and the machinesthat are'used in performing those operations, are frequently referred tohereinafter, in describing the present invention. Ihe usual practice istherefore now described as follows:-

First usual operation.The paver, so called, advances intermittently,this being a power machine that mixes the concrete, deposits it atdifferent places in the width of the roadway, and spreads it,approximately only, to the desired road surface.

Second usual operation-Close behind the paver a finishing machine, socalled, usually follows. This machine is also a power driven machine. Itmay better be described herein as a transverse finishing machine,because its screed lies transverse of the roadway, this namedistinguishing it from the present invention, which is a longitudinalfinishing machine. The screed of said transverse finisher reaches rightacross the roadway, its ends resting upon the forms at the edges of theroadway, whereby the depth of its out is regulated by said forms.

Said screed has an oscillatory movement, longwise of itself, and at thesame time it advances with the machine as a whole, along the roadway.Said screed is arched to conform to the crown desired for the roadway.

Third usual operation-After the said transverse finisher, ahand-operated treatment usually follows, and it is this hand operationthat the present invention is designed to replace. The

hand operation is as followsz-Two bridges stand across the roadway- Abull float" lies longwise of the roadway, in the gap between the twobridges. And two men, on the bridges, grasp plow handles attached to thefi'oat and work it,

entirely by hand power, its function being to smooth down theundulations left by the transverse finisher.

Fourth usual operation.Finally a belting machine, so called, usuallyfollows, in order to give a roughness to the actual surface, to providea grip for rubber tires.

As stated above, it is in the third of the foregoing four operationsthat the present invention is meant to be employed. That is. to say, itwill replace the hand-operated longitudinal screed of float by apower-operated longitudinal screed, for use in correcting the faultsleft by the transverse screed of the transverse finisher.

When the present invention is employed for said third operation, saidfirst, second and fourth operations will still be desirable, andwillstill be performed in the same way as hitherto, except that fewertreatments bythe transverse finisher, second operation" above, will thensuillce. Whereas it is now usually specified that said transversefinisher must return and advance over the same ground again, coveringthe ground perhaps as many as three times in all, it will then sufiicefor it to cover the ground once only. Thus a saving will be efiected inrespect of said second operation, in addition to advantages in theoperation which the present invention itself performs, namely, the thirdoperation.

Truth of the riding surface in the direction of trafiic, that is,longwise of the road, is obviously more important than truth in thecrosswise direction. And the present invention, by introducingmechanical accuracy into the longwise treatment of the road, suppliesthe desired truth in the longwlse direction, thus enabling the everincreasing stringency of the regulations of highway departments to bemet.

Another advantage is that, being power driven, the invention can dealwith concrete of a stifier consistency than the hand fioat can.Accordingly, a. longer time-interval can be allowed to precede it. Thusit may be timed to follow the transverse finisher after an intervalwhich allows the concrete to approach its initial set, by which timemuch of the excess water of the wetter batches of concrete deposited bythe paver will have had time to escape into the sub-grade or into theair, whereby the concrete as a whole will have become more uniform inconsistency, and consequently the tendency for hollows to be formed, dueto unequal final shrinking, subse-- quent to all operations, will bereduced.

Other advantages will appear in the course of the description.

In the drawings:

Fig. 1 is a plan of a complete machine with some minor parts broken awayor removed.

Fig. 2 is an end sectional elevation on line 2-2, Fig. 1, with someparts broken away and some parts removed.

Fig. 3 is a cross sectional elevation on line 3--3, Fig. 1, with somegearing removed.

Figs. 4 and 5 are details of the main-shaft reversing clutch shown inFig. 1, Fig. 4 being a plan, and Fig. 5 being an end view, both beingpartly in. section.

Fig. 6 is an end elevation showing detail of some of the gears of Fig.2.

Fig. 7 is a diagram, showing the general course travelled by the screedrelative to the direction of the road, the oscillatory movement of thescreed endwise of itself being here disregarded. Fig. 8 is a diagram,showing all of the three simultaneous movements of the screed, namely,

oscillating, and transverse of the road, and advancing along the road.

Figs. 9 and 10 show the retarding device which retards the forward endof the screed, Fig. 9 being a side sectional elevation, and Fig. 10being a front elevation.

Figs. 11, 12, and 1-3 are details of the shoe at the rear end of thescreed, and associated parts, including automatic lift-over mechanism.Of these'figures, Fig. 11 is a plan; Fig. 12 is a side elevation, thatis, viewed from the side of the screed, the view being sectional, online I2-l2, Fig. 13, and the hinged plate being removed; and Fig. 13 isa front elevation, that is, viewed longwise of the screed, partly insection.

Referring to the drawings:-

The action of the machine will be best understood by referring first tothe two diagrams, Figs. 7 and 8:--

In Fig. 7, the screed l, in position I, is ready to start. The roadway 2is to be finished or screeded, and the arrow 3 represents the directionof advance of the machine as a whole as it works, the main part of themachine at rear being here indicated by the charend 8 still having thesame tardiness. in relation to said rearward end 5.

At the point 9, the crosswise travel mechanism reverses, whereupon thesecond stroke of the machine begins. Said rearward end 5 then travels ashort distance to the left without said forward end 6 having begun totravel, until position III is reached, in which position said forwardend 6 slants as much to the right as originally it did to the left. Thenthe whole screed begins to move, and moves, at a constant slant, to theleft, treating the shaded parallelogram or diagonal zone l0, untilposition IV is reached. Then, at point II, reversal again takes place,and the third stroke of the machine begins, it now travelling again tothe right.

At position V the forward end of the screed again slants to the left, asit did at position I, and the treatment of the shaded parallelogram ordiagonal zone Ila begins, which treatment is, in the diagram,discontinued at position VI.

The overlapping of the zones is such that all parts of the road surface,after the machine has finished its first stroke, receive two treatmentsat least. In order to demonstrate this fact, said parallelogram ordiagonal zone l0 may be taken as an instance, as follows:-

Assume, then, that said second stroke of the screed has just beencompleted, during which stroke it has treated the whole of saidparallelogram l0, and has halted at said position IV. Said parallelograml0 may be said to consist of two triangles, namely, a lower triangle l3and an upper triangle i4, separated by the broken line i5. Thereforeboth of said triangles have Just received' a treatment, the result ofsaid second stroke. But said lower triangle i 3 had already received anearlier treatment during said first stroke of the screed, making twotreatments in triangle.

all for the lower triangle; and said upper triangle i4 is just about toreceive a second treatment, as part of said third stroke of the screed,which will make two treatments in all for the upper That is to say, thewhole of said parallelogram III has been, or will be as the machineproceeds, treated twice.

There is, moreover, a small portion of said parallelogram I! whichreceives a total of three. treatments, namely, the narrow strip liawhich lies between said broken line I! and the broken line It. But thereis no portion which receives less than two treatments.

Generalizing from the preceding two paragraphs, it is to be noted that,after the first stroke of the machine, no portion of the road surfacereceives less than two treatments. Also that the two treatments are fromalmost opposite directions, which is of great importance, as ishereinafter explained.

Also it is to be noted that sometimes the right-hand edge I! of thescreed is the screed's leading or cutting edge, and sometimes thelefthand edge is such.

Referring more particularly to Fig. 8:-

A movement not indicated in Fig. 7 is a constant oscillation of thescreed endwise of itself.-

That oscillation is indicated in Fig. 8, in which figure the point [9,chosen as an instance, in said screed i, will, if the machine isstarted, trace the path indicated by the line Ila, due to the threesimultaneous movements of the screed, namely, first, its movement oftranslation to the right, across said roadway 2; second, its movement ofadvance, along said roadway; and, third, its movement of oscillation,endwise of itself.

While a screed is being translated, sideways of itself, in its work, itmay push protruding stones in the direction of its translation, leavingholes in the concrete at rear of such stones. This is apt to happennotwithstanding the smoothing effect of any simultaneous oscillatorymovement of the screed, endwise of itself. But, if the screed can bemade to work back again over the same ground, in substantially theopposite direction, said holes will be filled up more effectively thanif the screed went back empty, and then covered the ground a second timein the original direction. Hence the importance of the fact demonstratedhereinabove that, in the present invention, the screed, in the regularcourse of its movements, treats all parts of the road surface twice,from substantially opposite directions.

'The object in retarding the forward end of the screed as described isthree-fold. First, it increases the tendency to push forward, as well assideways, relative to the road, the excess concrete which the workingedge of the screed dislodges. Second, it avoids an exact parallelism inthe ,two treatments aforesaid of the surface, thereby avoiding anytendency to accentuate, in the second treatment, any ridges and furrowsleft by the first treatment. And, third, it reduces the tendency of thepaving material near the rear end of the screed to escape round thatend, and thus to form a ridge across the pavement.

Trains or groups of gearing contained in the machine are as follows:

Referring more particularly to Figs. 1, 2, and 32- The engine 20 drivesthe power output shaft 2|, which, by means of suitable gearing, drivesthe first cross shaft 22, which in turn, by means of suitable gearing,drives the second cross shaft 28.

Said second cross shaft 28 actuates what may be described as the secondtrain of gearing, as follows:--

Said second cross shaft 23 drives the central bevel wheel 24, which isalways-in mesh with the 5 two bevel wheels 25 and 26. These wheels, co-

operating with the clutch gear hereinafter described, cause the mainshaft 21 to be driven in one direction or the other, there being nopause at neutral position. Said first cross shaft 22 actuates what maybe described as the first train of gearing, as follows:-

Said first cross shaft 22 by suitable gearing drives the sliding shaft29, Fig. 1, which, by means of the small pinion 30 at its end, drivesthe large pinion 3| when saldsliding shaft 29 is slid into gear by meansof the clutch lever 32, Fig. 3.

Said large'pinion 3| is integral with a sleeve 33 which sleeve has atone end the clutch dogs 34, and carries at its other end the sprocket35, which, by means of the chain 36 and sprocket .31, drives the sleeve38, which drives the travel shaft 39, which drives the travel wheels 46and 4|, which wheels, rolling respectively upon the forms 42 and 25. 43,placed at, the edges of said roadway 2, cause the whole machine eitherto advance in the di rection of the arrow 44, or to retreat.

Further details of the gearing in said two trains are given at the endof this specification.

The moving of the machine as a whole is accomplished as follows: v

When the engine is running, said first and second'cross shafts 22 and 23are both always running.

Said first train of gearing gears downward. Consequently, when saidfirst train is in gear with said large pinion' 3|, as hereinabovedescribed, the machine travels at its slower speed, and such slow travelis in one direction only, namely, the

40 forward direction.

But, when said sliding shaft 29 is out of gear with said large pinion3|, the clutch may be put into gear with said clutch dogs 34, whereuponsaid large pinion 3| will be caused to drive 45 said travel shaft 39 atits faster speed, to travel the machine at its faster speed, eitheradvancing w or retreating, according-to the direction in which said mainshaft 21 is running at the moment. The endwise oscillating of thescreed, hereinbefore described, is accomplished as follows:-

Said main shaft 21 has at its ends the cranks 48 and 49, actuating theconnecting rods 56 and 5|, causing the oscillator bar 52 to movebackward and forward of the roadway, whereby, with I A worm 56, uponsaid main shaft 21, gears into the worm wheel 51 running idle upon thescreed: chain driver-shaft 58 at the right of the machine;

70 When the clutch 59 is thrown into gear with said worm wheel 51, saiddriver shaft is caused to revolve in one direction or the other,according to the direction in which said main shaft 21 happens to berunning at the moment.

76 Sprockets 69 and 6|, mounted upon said driver shaft 56, operate therearward and forward screed-chains 62 and 63, which chains pass oversprockets- 63a and 63b mounted upon a driven shaft 64, provided at theleft of the machine. The ends of said rearward screed-chain 62 are at- 5tached at points 65 and 66, Fig. 3, to the rearward shoe 61 at therearward end of said screed And, similarly, the ends of said forwardscreed-chain 63 are attached to the forward By these means the screed istranslated from side to side of said roadway 2, its direction, either toright or to left of. said roadway, depending upon the direction ofrotation, at the moment, of said driver shaft 53, which in turn depends15 for its direction upon the direction, at. the mo-- ment, of said mainshaft 21.

second, a movement of oscillation of the screed 30 endwise of itself andthird, a movement of translation of the screed across the roadway. Andit will be noted that all three of such movements can be caused to occursimultaneously.

The engine and most of the gearing above described are carried on thenon-continuous platform 68a, which is carried by the frame ,69 of themachine.

The reversing of the direction of translation of the screed, from oneside of the road to the 40 other, at the right moment, is accomplishedas follows Referring more particularly to Figs. 1, 4, and V In Fig. 4the full lines show the reversing mech- 45 anism when on dead centre andjust about to spring over; and the dotted lines show the condition afterthe spring-over has taken place.

Said rearward screed chain 62 .passes through the channel-shaped, guide10, and carries the 50 chain stop 1|. Said channel 10 is attached bymeans of the plate 12 to the sliding block 13 into which block ispivoted the vertical post 14, having upon it the swinging horizontal arm15.

When said stop 1| during the course of its travel upon said chain in thedirection of the arrow 12a, Fig. 4, meets said channel, it pushes saidchannel along in front of it, meantime compressing the spring 16 untilsaid swinging arm 1 15 is in line with the clutch arm 11, a dead-centrecondition having been thereby reached. A momerit later, whilethe chainstill travels, the

spring-over takes place, causing said block 13 to slide a little furtherto the right, as shown by the dotted position of said block in Fig. 4,where it is stopped by the block-stop 19, the block carrying with itsaid channel 10, and said post 14, and said swinging arm 15.

The spring meantime causes said swinging arm 15 to assume its dottedposition, Fig. 4,. which in 70 turn causes said clutch arm 11 toassumeits dotted position, which in turn, by means of its downwardlyprojecting finger 82, causes the ,clutch member 83 toslide out ofengagement with said bevel wheel 25 and into gear with said -bevel wheel20, (the new position of said clutch member being not shown in thedrawings) thereby causing the direction of said main shaft 21 to bereversed.

Immediately thereupon, said chain 02 travels in the opposite direction,carrying said chain stop 1I away from said channel, and eventuallybringing a second chain stop, not shown, to push the channel at itsother end, and to thereby again reverse the movement at the rightmoment.

Said clutch arm 11 is pivoted at 84. Attached to it is the swivellingeyelet 05, through which said swinging arm 15 is free to run.

In practice, a hand-operated mechanismis Fig. 1.

The retarding of the forward end of the screed hereinbefore described,is accomplished as follows:-

Referring more particularly to Figs. 1, 9, and 10:-

Said screed-chain driver-shaft 59 has its said forward sprocket 0|running loosely upon it, while. near said sprocket, the gapped wheel 90is fixed rigidly to said shaft. The pin 9|, projecting in axialdirection from said sprocket, enters the arcuate gap 92 provided in saidwheel 90.

When said driver shaft 58 is put in motion in either direction, the'fact that said forward sprocket 6| is loose upon it causes said forwardscreed chain 63 to remain without motion until said pin 9| has reachedeither end of said gap 02,

as shown by the two dotted positions of said pin in Fig. 10, whereuponmotion of said screedchain will begin, because said sprocket GI willthen be driven by said gapped wheel 90.

Upon said driven shaft 64, whereas the rearward sprocket 63a is rigid,the forward sprocket 83b is loose, permitting the latter to accorditself to any lost motion of said driver-sprocket GI. Accordingly, saidforward screed-chain 93, attached at its ends to said forward shoe 68 ashereinbefore described, transmits the movements of said sprocket 6i,including the losses in motion of said sprocket, to said shoe,therebyeffecting the desired retarding of the forward end of the screed.

Mechanism for governing the working'depth of the screed is as follows:

Referring first more particularly to Figs. 1, 2, and 3, the reartemplate 95 and the forward template 96, Fig. 1, are rigid membersarched to the desired road contour, as shown in side view in Fig. 3, andare attached to contiguous parts of i said frame 69. Said rearward andforward shoes 61 and G8 are supported respectively .by said templates,upon which they are free to run or slide; and said screed-chains 62 and63 pull said shoes either to the right or to the left across theroadway, as hereinbefore described.

By these means, the weight of the screed is carried by the templates,and the templates, in turn, are carried by, or are a part of, themachine itself. And it follows that the regulating of the depth of thecut of the screed is a matter relative to the templates, or to the frameof the machine, quite independently ofthe forms.

This arrangement is in contrast with that of the transverse finishingmachine described in Second usual operation" above, in which the screedrests, not upon the machine, but upon the forms at theedges of the road.That transverse finisher has also further disadvantages as follows:(l)Any unevennesses in the forms directly affect the screed, causing ridgesand furrows crosswise of the roadway, whereas'in the present inventionthe length of the wheel-base of the machine softens said unevennesses ofthe forms;

(2) In the transverse machine, the fact that the forms which carry thescreed, and the machine that moves the screed, are separate entitiestends to cause a vibration in the transmitting of the motion, resultingin crosswise furrows; and (3) In the transverse machine, the screed mustbe a long one, because it must span the whole roadway, and thereforemust be correspondingly strongly braced and heavy, to prevent anyspringing of its arch during work, which would cause untruth in the roadcontour; whereas in the present invention the screed can be as short asmay be found convenient.

That-is to say, several marked disadvantages, inherent when the screedrides upon the road "forms, are eliminated by the present invention,

- in which the screed rides upon templates, which in that direction;whereas, in the present invention, the movement of the screed sidewaysof itself is relative to the frame of the machine.

An automatic lift-over" mechanism, for preventing concrete from beingwiped off, over the forms, at the sides of the road, is as follows:1'3Referring more particularly to Figs. 11, 12 and In those figures thescreed I, with its rearward shoe 61, is shown near the other end of itscross: wise travel, as compared with Figs. 1 and 3.

Said rear template 9! is attached to a contiguous portion of said frame69 of the machine, Fig. 12, as hereinbefore related. Also attached tosaid frame is the bracket 91 from which are suspended the rigid plate90, Fig. 13, and the hinged plate 99. The latter ishinged to said rigidplate by the hinge I00, and is permitted to rise upward by the bolts IOIpassing freely through the slots I02 in said bracket 91. I

Upon said template 95 said rearward shoe 61 slides, ashereinabovedescribed, during most of the Journey of the screed from side to side ofthe roadway, at which times. the screed forms the concrete to the lineI03, Fig. 13, as shown by the dotted position VII of said screed I.

Rising from said shoe are brackets I05 and f I08 carrying inwardlyprojecting lips I01 and I09.

Referring to Fig. 13:-When the screed I is at said dotted position VII,said lip I 01 will be at its dotted position VII. Thereafter, while themovement of the mechanism progresses further to the right, pulled bysaid rearward screed chain 82, said lip I01 will slide upward upon saidhinged plate 99 until it reaches its full-lined position aforesaid. Itwill then have'lifted said shoe 61 to its suspended position, as shownin full lines in the drawings, and, at the same time, will have liftedsaid screed I from said dotted position VII p a,os4,oos to itsfull-lined position, during which time said screed will have formed theconcrete I09 to the line III! at a higher elevation than the dotted lineIII, to which it is'desired, eventually, to form it.

Continuing the whole movement still further to the right, said lip-IIi'I will keep said shoe suspended until said lip has passed beyondsaid rigid plate 98. Thereupon the ,whole 01' the suspended mechanismwill drop. That'is to say, said shoe 8! will again rest slidably uponsaid template 95, while said lip I01 and screed I will be in the dottedposition VIII. The automatic reversal of the direction of sideway travelof the screed,

in so doing, passing along said dotted line III,

while said lip I01, leaving its said dotted position VIII, will passunder said rigid plate 99,.lifting the latter to enable it so to do, thelatter thereafter dropping to its normal position ready fora repetitionof the process. v A corresponding automatic lift over mechanism isprovided at the other end of said rearward template 95. Also themechanisms are repeated in respect of said forward template 96.

By these means such amount of concrete as is pushed along by that edgeof the screed which is, at the time, the working edge, is not swept overthe form, but is swept inward of the roadway, to fill up low places.

Some further details of Figs. 11, i2, and 13 are as follows:---

A U-bracket I I2 suspends the screed by means of the adjustablehanger-bolts II 3 from the axle II4 of the wheels H5; running on saidshoe 61. Bythese means the height of the screed relative to the shoe,andhence relative to the template, is adjusted, while the wheelsfacilitate the oscillation aforesaid of the screed endwise of itself.

Also, the employment of said U-bracket II 2 makes it possiblefor saidtemplate to stand at a convenient clearance above the concrete, whilenone, the less carrying the weight of the screed.

as aforesaid, consists of a worm I I9, carried upon said "shaft 2i,gearing into the worm-wheel I20 on said cross shaft 22.

The gearing aforesaid, as between said first and second cross-shafts 22and 23, consists of sprockets I2I and I22 on said shafts respectively,geared together by the chain I23.

The gearing aforesaid, as vbetween said =first cross-shaft 22 and saidsliding shaft 29, consists of the worm- I24 carried upon said crossshaft, gearing into the worm-wheel I25 carried upon the jack-shaft I26,which shaft carries also the pinion I21, gearing into the pinion I28upon said sliding shaft.

I claim:

1. A road finishing machine 7 comprising a screed, means for causingsaldscreed to automatically treat twice, from substantially oppositedirections, a portion of a roadway. and means for causing the angularset 'of the leading edge of said screed, during said second treatment,to be substantially out of parallel with the angular set which had beenemployed by the leading edge during said first treatment.

2. A road finishing machine comprising a screed, means for continuouslytranslating and returning said screed in a direction substantiallytransverse of its length while such screed operates, and automaticretarding means for causing the front end of'said screed to lag behindits rear end during such translations and returns.

3. A road finishing machine comprising, when in position upon a roadway,a screed lying substantially longwise of the roadway, means fortranslating said screed from side to side of the roadway, and automaticmeans for raising said screed above its operating elevation when nearthe end of a translation and for lowering same ,again before its returntranslation, whereby excess paving material may be wiped inward of theroadway rather than be .wiped off the roadway.

4. A road finishing machine comprising a. machine frame, a screed, meansfor translating said screed in a direction substantially transverse ofits length and for returning it in the opposite direction,'a lipattached to said screed, and a hinged sloping plate attached to saidframe, said plate being adapted to co-operate with said lip to liftsaidscreed above its working elevation during translation in said firstdirection, and being adapted to allow said lip to pass under it duringsaid return. I

5. A road finishing machine comprising a screed, a shoe at a higherelevation than said screed, a bracket attached to said screed andsupported by said shoe, a track along which said shoe is adapted to betravelled in a direction crosswise of said screed, and a guide extendingdownward from said shoe adapted to prevent tilting of said screedsideways of itself during operation.

6. .The method of making a concrete road and truing its surface whichconsists in spreading concrete to a first approximation in respect oftruth of surface, and thereafter reaching a second and a thirdapproximation respectively by means of two cutting operations free frompress- 'ing operations, such cutting operations being performed in eachcase by a mechanically operated screed having a. cutting edge guided byspring-free means to cut to a definite cutting plane in respect ofdepth, each such screed accordingly cutting off such concrete as standsas excess above said cutting line, and pushing said excess before it,said two screeds lying at substantially different angles in relation tothe direction of the roadway.

7. In a road'surface truing machine, a slicing and pushing screedadapted to slice off the high parts from a mass of plastic road materialwithout pressing down upon the residue of such.-

its

mass, and to push such sliced off material before ,I

8. In a road surfacetruing machine, a slicing and pushing screed, andmeans for translating said screed in either direction approximatelytransverse of its length, said screed being adapted to sliceoif thehighplaces from a mass of plastic road material without pressing downupon the residue of such mass, and to-push such sliced of! materialbefore it, when said screed is translated in either of said directions.

10 9. A road pavement truing machine comprising, when in operatingposition above 'a roadway, a cutting screed, lying approximately atleast longwise of the roadway mechanically operated means forcontinuously translating said screed from sideto side of the roadway,-against the resistance of its cutting, and mechanical,

- non-elasticmeans for automatically controlling translation in thedirection of either of said faces, to cut a shaving of substantial depthfrom a high part of a plastic mass of road material, to push such slicedof! material before it, and to allow substantially allof same to dropdownward to fill a depression, said 'screedduring such operations notpressing downward upon the material to displace it.

10. A road pavement truing machine as claimed in claim 9, said sidefaces rising abruptly and in substantially a straight line from saiddownward face, whereby said sliced ofi material may befree to drop themore cleanly away from saidfaces.

11. A road pavement truing "machine as claimed in claim -9, saidtranslating -means acting in a. plane substantially close to the planeof travel of the bottom of said screed, whereby tendency to tilt saidscreed, during said translation of same against the resistance of saidmaterial, is a 12. A road pavement truing machine as claimed in claim9,. said depth controlling means comprising templets transverse of theroadway; means movable along said templets supporting the ends of saidscreed withoutthe intervention of springs, and means for preventingtilting of said screed relative to said templets in theldirectionlongwise of said templets.

13. A road pavement truing machine as claimed in claim 9, said depthcontrolling means comprising templets transverse of the roadway, shoessupporting the screed without the intervention of springs, said shoesbeing adapted to be moved along said 'templets and having substantiallengthof bearing along said templets to. prevent their tilting longwisethereof, and

means carried by said shoes for substantially preventing the tilting ofsaid screed relative to said show.

'. 14. A road finishing machine comprising when in operating positionabove a roadway a screed,

means-for continuously translating and returning said screed in adirection substantially transverse of its length while such screedoperates,

and.,automatic,retarding' means for causing the.

front end of said screed to lag behind the rear end during suchtranslations and returns, said retarding means comprising a horizontalshaft at each side of the screedfa sprocket it each end of each saidshaft, a front and rear chain passing respectively around the front andrear pairs of sprockets and connected to means movable with' the frontand rear ends respectively of said screed, whereby said chains areadapted .to translate said screed when said shafts are revolved, saidfront sprockets being loose upon said shafts, said retarding meansfurther comprising a wheel rigid: upon each said shaft adjacent saidfront sprockets, and mechanismfor causing lost motion between said frontsprockets. T

15. A road finishing machine comprising a screed, means for translatingsaid screed'crosswise of the roadway, and means for reciprocating saidscreed longwise of the roadway during said wheels and said translation,said reciprocating means com prising a bar extending crosswise of theroadway for substantially the full width of the roadway,

a front stop and a rear stop located on said screed, 'slidablealong'said bar, and means operating at the ends of said bar to give saidbar a reciprocating movement longwise of the roadway; I e V 16. A roadfinishing machine as claimed in I claim It, guides being provided forguiding said bar during'said reciprocation, whereby said bar isprevented from exerting angular pressure downward upon said screed.

17. In a road finishing machine, a mechanically operated screed, andmechanical means for translating said screed from 'sideto side of aroadway, .saidmeans comprising shoes, draft ele-.'

ments' attached to said shoes, and brackets at the ends of the'screed,said brackets and screed constituting a unit, the brackets resting bythe force -'of gravity upon the shoes, whereby said unit can be removedfrom the machine without any unfastening.

I 18. The method of making a concrete road, which includes the steps ofspreading concrete to a first approximation'of the truth of'surface tobe obtained, then subjecting. the concrete in a cutting and pushingaction at its surface portion, the direction of said cutting and pushingbeing substantially crosswise of the roadway, so

as to effect a further approximation of the'final truth of surface to beobtained, and at the same time to cause a substantial proportion of theconcrete so cut to he pushed along while lying upon the main laidbodythereof, shifting crosswise of the roadway, thereby to fill voids ordepressions in the surface portions of the main body of concrete.

19. The method as claimed in claim 18, said cutting and pushing furthercausing said substantial proportion of the concrete to be moved to andfro crosswise of the road without being forced off the edge of the mainbody of concrete the surface of which is being brought to final truth oraccuracy. I

20. The method of making a concrete road and truing its surface, whichconsists in spreading concrete-to a first approximation in respect oftruth of surface, and thereafter cutting the upper-surface portions ofthe concrete in a direction crosswise of the roadway, at the same timeshifting the cut portions in a direction laterally across the roadwaywhile lying upon the

